JP2017109427A - Three-dimensional object molding apparatus, three-dimensional object molding method, and control program for three-dimensional object molding apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide technology capable of easily controlling a density in a support part of a three-dimensional object.SOLUTION: A three-dimensional object molding apparatus includes: a dot forming part for forming dots constituting a three-dimensional object as a target for molding and a support part supporting the three-dimensional object; and a control part for controlling molding of the three-dimensional object and the support part by the dots to be formed. In the support part, the control part disposes dots in a voxel group representing the support part so as to form a support structure for supporting the three-dimensional object based on a dither mask and an input value representing a formation rate of dots in a voxel included in the voxel group. The control part may dispose dots in a voxel group representing the support part so as to form the support structure for supporting the three-dimensional object, by performing a halftone process of diffusing an error into an unconverted voxel with respect to an input value representing a formation rate of dots in a voxel included in the voxel group.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a three-dimensional object formation apparatus, a three-dimensional object formation method, and a control program for a three-dimensional object formation apparatus.

  A 3D (three-dimensional) printer is known as a three-dimensional object modeling apparatus. 3D printers that use ink that is cured by ultraviolet irradiation, for example, form dots by discharging droplets of ultraviolet curable ink to cure by ultraviolet irradiation to form a modeling layer, and stack the modeling layer. Shape a three-dimensional object. Patent Document 1 discloses a method for forming an orthogonal lattice-like support that supports an overhang portion of a modeled object created by an optical modeling method. The modeled object and the support are laminated in the Z-axis direction with a unit photocuring layer formed so as to have a thickness on the gravity direction axis (Z-axis) and a shape on an XY plane orthogonal to the Z-axis. Formed. A predetermined gap is provided between the modeled object and the support on the XY plane.

JP-A-8-25487

However, since the support is only formed in an orthogonal lattice pattern regardless of the shape of the overhang portion, the support of the overhang portion may be insufficient or excessive material may be consumed for forming the support. .
The above problems are not limited to 3D printers that use ultraviolet curable inks, but three-dimensional object modeling apparatuses that use visible light curable inks that are cured by visible light irradiation, and thermosetting inks that are cured by heating. Various technologies such as a three-dimensional object forming apparatus to be used and a three-dimensional object forming apparatus using a thermoplastic material also exist in the same manner.

  In view of the above, one of the objects of the present invention is to provide a technique capable of easily controlling the density of the support portion of the three-dimensional object.

In order to achieve one of the above objects, the present invention provides a three-dimensional object to be modeled, and a dot forming part for forming dots constituting a support part that supports the three-dimensional object,
A control unit that controls the modeling of the three-dimensional object and the support unit by the formed dots;
A three-dimensional object shaping apparatus comprising:
In the support unit, a support structure that supports the three-dimensional object is formed in the support unit based on an input value representing a dot formation rate in a voxel included in the voxel set representing the support unit and a dither mask. In this manner, the dots are arranged in the voxel set.

In addition, the present invention provides a three-dimensional object to be modeled, and a dot forming part for forming dots constituting a support part that supports the three-dimensional object,
A control unit that controls the modeling of the three-dimensional object and the support unit by the formed dots;
A three-dimensional object shaping apparatus comprising:
The control unit performs, in the support unit, halftone processing for diffusing an error into unconverted voxels with respect to an input value indicating a dot formation rate in a voxel included in the voxel set representing the support unit. The dot is arranged in the voxel set so that a support structure for supporting the three-dimensional object is formed.

Furthermore, this invention uses the dot formation part for forming the solid object of modeling object, and the dot which comprises the support part which supports this solid object, The said solid object and the said support part by the dot formed are used. A three-dimensional object modeling method for modeling,
In the support unit, dots are formed so that a support structure for supporting the three-dimensional object is formed based on an input value representing a dot formation rate in a voxel included in the voxel set representing the support unit and a dither mask. It has the aspect which arrange | positions in the said voxel aggregate | assembly and models the said solid object and the said support part.

Furthermore, this invention uses the dot formation part for forming the solid object of modeling object, and the dot which comprises the support part which supports this solid object, The said solid object and the said support part by the dot formed are used. A three-dimensional object modeling method for modeling,
The support unit performs halftone processing for diffusing an error into unconverted voxels with respect to an input value indicating a dot formation rate in a voxel included in the voxel set representing the support unit, thereby obtaining the three-dimensional object. It has the aspect which arrange | positions a dot in the said voxel group | set so that the support structure to support may be formed, and shape | molds the said solid object and the said support part.

Furthermore, the present invention includes a three-dimensional object to be modeled and a dot forming part for forming dots that constitute a support part that supports the three-dimensional object, and the three-dimensional object by the formed dots and the support part. A control program for a three-dimensional object forming apparatus for controlling modeling,
In the support unit, dots are formed so that a support structure for supporting the three-dimensional object is formed based on an input value representing a dot formation rate in a voxel included in the voxel set representing the support unit and a dither mask. It has a mode for causing a computer to realize the function of arranging in the voxel set.

Furthermore, the present invention includes a three-dimensional object to be modeled and a dot forming part for forming dots that constitute a support part that supports the three-dimensional object, and the three-dimensional object by the formed dots and the support part. A control program for a three-dimensional object forming apparatus for controlling modeling,
The support unit performs halftone processing for diffusing an error into unconverted voxels with respect to an input value indicating a dot formation rate in a voxel included in the voxel set representing the support unit, thereby obtaining the three-dimensional object. It has a mode in which a computer realizes a function of arranging dots in the voxel set so that a supporting structure to support is formed.

  The aspect mentioned above can provide the technique which can control easily the density of the support part of a solid object.

  Furthermore, the present invention provides a three-dimensional object modeling system including a three-dimensional object modeling apparatus, a control method for a three-dimensional object modeling apparatus, a control method for a three-dimensional object modeling system including this control method, a control program for a three-dimensional object modeling system, and a three-dimensional object modeling apparatus. And a computer-readable medium in which a control program for a three-dimensional object modeling system is recorded. The aforementioned apparatus may be composed of a plurality of distributed parts.

The functional block diagram which shows the structural example of a solid-object modeling apparatus. The figure which shows the modeling example of a solid object and a support part typically. The figure which shows the example of a modeling processing apparatus typically. FIG. 3 is a diagram schematically illustrating an example of arrangement of nozzles of a recording head. The figure which shows typically an example of the concept which produces | generates discharge of a droplet, or non-discharge of a droplet from a drive signal. The flowchart which shows the example of modeling processing. The figure which shows a solid object and a support part typically. The figure which shows the structural example of a dither mask typically. The figure which shows typically the example which matches a dither mask with a modeling layer. The perspective view which shows typically the example of the support structure formed in a support part. The figure which shows typically the example which made low the dot density of the 2nd site | part close | similar to the part by which a solid object is supported rather than a 1st site | part in a support structure. The flowchart which shows the example of the support part halftone process using a dither mask. The flowchart which shows the example which selects a dither mask according to a setting direction in support part halftone pre-processing. The flowchart which shows the example which performs the rotation process of a dither mask in a support part halftone pre-process. The flowchart which shows the example which performs the rotation process of the data before and behind a halftone process in the alternative process of the support part halftone process of FIG. The figure which shows typically the example which performs the rotation process of the data before and behind a support part halftone process. The figure which shows typically the example which changes a dot density according to the information regarding the part by which a solid object is supported in a support structure. The figure which shows typically another example which changes dot density according to the information regarding the part by which a solid object is supported in a support structure. The flowchart which shows the example of a support part modeling layer former data production | generation process. The flowchart which shows another example of a support part modeling layer former data generation process. The figure which shows typically the error diffusion method for forming a support structure. The figure which shows the example of the distribution rate of an error typically. The flowchart which shows the example of the support part halftone process by an error diffusion method.

  Embodiments of the present invention will be described below. Of course, the following embodiments are merely examples of the present invention, and all the features shown in the embodiments are not necessarily essential to the means for solving the invention.

(1) Overview of this technology:
First, the outline of the present technology will be described with reference to FIGS. 1 to 23 are schematic views, and the drawings may not be consistent.

[Aspect 1]
A three-dimensional object modeling apparatus 100 illustrated in FIG. 1 and the like includes a three-dimensional object Obj to be modeled and a dot forming unit (for example, a head unit) for forming the dots DT constituting the support part SP0 that supports the three-dimensional object Obj. 3) and a control unit U1 that controls modeling of the three-dimensional object Obj and the support portion SP0 by the formed dots DT. Based on the input value V2 representing the formation rate of dots DT in the voxels Vx included in the voxel set representing the support unit SP0 and the dither mask (for example, the dither matrix DZ), the control unit U1. The dots DT are arranged in the voxel set so that a support structure ST0 that supports the three-dimensional object Obj is formed.

  In the first aspect, the three-dimensional object Obj is supported by the support portion SP0 based on the input value V2 representing the formation rate of the dots DT in the voxels Vx included in the voxel set representing the support portion SP0 and the dither mask (DZ). A support structure ST0 is formed. For example, when the input value V2 is changed so as to increase the dot DT formation rate, the density of the dots DT of the support structure ST0 increases. When the input value V2 is changed so as to reduce the formation rate of the dots DT, the density of the dots DT of the support structure ST0 decreases. Therefore, this aspect can provide a three-dimensional object forming apparatus that can easily control the density of the support part of the three-dimensional object.

[Aspect 2]
As exemplified in FIG. 21 and the like, the control unit U1 has an error with respect to the input value V2 representing the formation rate of the dots DT in the voxel Vx included in the voxel set representing the support unit SP0 in the support unit SP0. Dots DT may be arranged in the voxel set so as to form a support structure ST0 that supports the three-dimensional object Obj by performing a halftone process in which ER is diffused into unconverted voxels. In this aspect, by performing halftone processing for diffusing the error ER to unconverted voxels with respect to the input value V2 representing the formation rate of the dots DT in the voxels Vx included in the voxel set representing the support part SP0, A support structure ST0 that supports the three-dimensional object Obj is formed in the support part SP0. For example, when the input value V2 is changed so as to increase the dot DT formation rate, the density of the dots DT of the support structure ST0 increases. When the input value V2 is changed so as to reduce the formation rate of the dots DT, the density of the dots DT of the support structure ST0 decreases. Therefore, this aspect can also provide a three-dimensional object forming apparatus that can easily control the density of the support part of the three-dimensional object.

  Here, the voxel is a virtual three-dimensional figure for representing a space in which dots can be formed. A voxel set (Voxel-set) is a collection of a plurality of voxels.

[Aspect 3]
As illustrated in FIG. 10 and the like, the support structure ST0 may be one or more columns K0 that support the three-dimensional object Obj. The number NW1 of columns (for example, columns K1 to K8) whose length in the first direction W1 in the cross section is longer than the length in the second direction W2 intersecting the first direction W1 is the length in the second direction W2 in the cross section. May be greater than the number NW2 of struts longer than the length in the first direction W1. Since the strength of the support structure ST0 in the first direction W1 can be higher than the strength of the support structure ST0 in the second direction W2, this aspect provides a technique that can efficiently secure the strength of the support structure of the three-dimensional object. be able to.

Here, in the dither mask (DZ), the number NW1 of columns (for example, columns K1 to K8) whose length in the first direction W1 is longer than the length in the second direction W2 is the length in the second direction W2. May be a dither mask having directivity that makes the number NW2 longer than the length of the support columns longer than the length of the first direction W1. In the support unit SP0, the control unit U1 assigns the dot DT to the voxel group so that the one or more columns K0 are formed based on the input value V2 and the dither mask (DZ) having directivity. You may arrange in.
Further, the halftone process (illustrated in FIGS. 21 to 23) for diffusing the error ER causes the ratio of diffusing the error ER in the first direction W1 to be larger than the ratio of diffusing the error ER in the second direction W2. Processing is also acceptable. The control unit U1 causes the ratio of diffusing the error ER in the first direction W1 with respect to the input value V2 in the support unit SP0 to be larger than the ratio of diffusing the error ER in the second direction W2. Dot DT is arranged in the set of voxels so that the one or more struts K0 are formed by performing a halftone process having directivity to diffuse the error ER to unconverted voxels (for example, voxels PX1 to PX4). May be.
Of course, a case where NW1 ≦ NW2 is also included in the present technology.

[Aspect 4]
As illustrated in FIG. 2 and the like, the control unit U1 may form the three-dimensional object Obj and the support part SP0 by laminating the formation layer LY of the formed dots DT. Further, the control unit U1 connects the dots DT in the first direction W1 in the modeling layer LY in the support unit SP0 as compared to the second direction W2 intersecting the first direction W1 with respect to the input value V2. Dots DT may be arranged in the voxel set so that the support structure ST0 as illustrated in FIG. 10 and the like is formed by performing easy halftone processing. Since the strength of the support structure ST0 in the first direction W1 can be higher than the strength of the support structure ST0 in the second direction W2, this aspect provides a technique that can efficiently secure the strength of the support structure of the three-dimensional object. be able to.

Here, as illustrated in FIG. 8, the dither mask (DZ) causes the dots DT to move in the first direction W1 (X direction in FIG. 8) compared to the second direction W2 (Y direction in FIG. 8). It may be a dither mask having directivity that facilitates connection. The control unit U1 arranges dots DT in the voxel set so that the support structure ST0 is formed based on the input value V2 and the dither mask (DZ) having directivity in the support unit SP0. May be.
Further, in the halftone process for diffusing the error ER (illustrated in FIGS. 21 to 23), the ratio of diffusing the error ER in the first direction W1 (for example, the X direction in the distribution ratio RD1) is set to the second direction W2 (for example, The distribution ratio RD1 may be a process for making the error ER larger than the ratio of diffusing the error ER in the Y direction). The control unit U1 has a ratio of diffusing the error ER in the first direction W1 with respect to the input value V2 in the modeling layer LY in the support unit SP0 than the ratio of diffusing the error ER in the second direction W2. The dot DT may be arranged in the voxel set so that the support structure ST0 is formed by performing a halftone process having directivity for diffusing the error ER to unconverted voxels so that the error ER is increased.

[Aspect 5]
As illustrated in FIGS. 15 and 16, the control unit U <b> 1 compares the second direction W <b> 2 that intersects the first direction W <b> 1 with respect to the input value V <b> 2 in the modeling layer LY in the support portion SP <b> 0. A process of performing halftone processing that facilitates connection of dots DT in one direction W1, and rotating the data obtained by the halftone processing so that the first direction W1 is directed to a setting direction DS1 that actually prioritizes connection of dots DT. , The dots DT may be arranged in the voxel set so that the support structure ST0 is formed. In this aspect, since the strength of the support structure ST0 in the setting direction DS1 that actually gives priority to the connection of the dots DT can be higher than the strength of the support structure ST0 in the direction that intersects the setting direction DS1, the support structure of a three-dimensional object It is possible to provide a technique capable of efficiently ensuring the strength of the.

[Aspect 6]
As illustrated in FIGS. 17 to 19, the control unit U1 includes the support structure ST0 having a density based on information on a portion (for example, the overhang portion OB2) supported by the support portion SP0 in the three-dimensional object Obj. The input value V2 may be set so as to be formed. In this aspect, the support structure ST0 having a density corresponding to the portion (OB2) supported by the support portion SP0 of the three-dimensional object Obj is formed by setting the input value V2 representing the formation rate of the dots DT. A suitable technique for efficiently ensuring the strength of the support structure of the object can be provided.
Here, the information regarding the part supported by the support part includes the weight of the part, the height of the part, the area of the part, and the like.

[Aspect 7]
As illustrated in FIG. 11 and the like, the support part SP0 is closer to the three-dimensional object Obj than the first part SP1 in the first part SP1 and the direction (Z direction) stacked on the first part SP1. You may have 2nd site | part SP2. As illustrated in FIG. 20, the control unit U1 sets the dots DT so that the density of the dots DT in the second part SP2 is lower than the density of the dots DT in the first part SP1 in the support part SP0. You may arrange | position to the said voxel set. In this aspect, the density of the dots DT of the second part SP2 closer to the three-dimensional object Obj than the first part SP1 is lower than the density of the dots DT of the first part SP1 in the support part SP0. It can be easily removed.

[Aspect 8]
In the three-dimensional object modeling method illustrated in FIGS. 6 to 23, etc., in the support portion SP0, an input value V2 representing the formation rate of dots DT in the voxel Vx included in the voxel set representing the support portion SP0 and a dither mask ( DZ), the three-dimensional object Obj and the support portion SP0 are formed by arranging the dots DT in the voxel set so that the support structure ST0 that supports the three-dimensional object Obj is formed. This aspect can provide a three-dimensional object forming method that can easily control the density of the support part of the three-dimensional object.

[Aspect 9]
The three-dimensional object modeling method illustrated in FIGS. 6 to 23 and the like has an error with respect to the input value V2 representing the formation rate of the dots DT in the voxel Vx included in the voxel set representing the support portion SP0 in the support portion SP0. By performing a halftone process for diffusing ER into unconverted voxels, the three-dimensional object Obj and the support are arranged by arranging dots DT in the voxel set so as to form a support structure ST0 that supports the three-dimensional object Obj. Form part SP0. This aspect can also provide a three-dimensional object forming method that can easily control the density of the support portion of the three-dimensional object.

[Aspect 10]
The control program PR0 (for example, the control programs PR1 and PR2) of the three-dimensional object formation apparatus 100 illustrated in FIG. 1 and the like has the dot DT in the voxel Vx included in the voxel set representing the support portion SP0 in the support portion SP0. Based on the input value V2 representing the formation rate and the dither mask (DZ), the computer realizes a function of arranging the dots DT in the voxel set so that the support structure ST0 that supports the three-dimensional object Obj is formed. This aspect can provide a control program that can easily control the density of the support portion of the three-dimensional object.

[Aspect 11]
The control program PR0 (for example, the control programs PR1 and PR2) of the three-dimensional object formation apparatus 100 illustrated in FIG. 1 and the like has the dot DT in the voxel Vx included in the voxel set representing the support portion SP0 in the support portion SP0. By performing halftone processing for diffusing the error ER into unconverted voxels with respect to the input value V2 representing the formation rate, the dot DT is set to the voxel group so that the support structure ST0 that supports the three-dimensional object Obj is formed. Make the computer implement the function to be placed in This aspect can also provide a control program that can easily control the density of the support portion of the three-dimensional object.

(2) Specific example of the three-dimensional object forming apparatus:
FIG. 1 illustrates a configuration of a three-dimensional object forming apparatus 100 including a modeling processing apparatus 1 and a host device 9 as a configuration example of the three-dimensional object modeling apparatus. FIG. 2 schematically shows a modeling example of the three-dimensional object Obj and the support part SP0. FIG. 3 schematically shows an example of the modeling processing apparatus 1. Examples of the three-dimensional object Obj and the support part SP0 are also schematically shown in FIG. Y shown in FIGS. 2 and 3 does not mean yellow, but represents the Y direction. The X, Y, and Z directions shown in FIGS. 2 and 3 are assumed to be orthogonal to each other, but the present technology also includes a case where they are not orthogonal as long as they intersect each other. The modeling processing apparatus 1 shown in FIG. 1 forms a modeling layer LY with, for example, a predetermined thickness ΔZ from the dots DT formed by the discharged liquid LQ, and stacks the modeling layer LY to thereby form the three-dimensional object Obj and the support unit. Model SP0. Accordingly, when there is a portion where a space is generated below the three-dimensional object Obj, such as the overhang portion OB2, the support portion SP0 is required under the portion. In this specific example, the support structure ST0 is created as uniformly as possible with as little material (supporting ink LQ2) by performing halftone processing such as dithering to create the support structure ST0 of the overhang portion OB2. . The host device 9 shown in FIG. 1 generates modeling layer data FD that defines the shape and color of the three-dimensional object Obj and the support part SP0.

  The host device 9 includes a display operation unit 91, a model data generation unit 92, a modeling data generation unit 93, and a storage unit 94, and the operation of each unit is controlled by a CPU (Central Processing Unit) (not shown). The display operation unit 91 includes a display and operation input devices such as a keyboard and a pointing device. The model data generation unit 92 generates model data Dat, which will be described later, and an intensity index value ST as necessary. The modeling data generation unit 93 includes a halftone processing unit 95, and generates modeling layer data FD based on the model data Dat and the intensity index value ST. This modeling layer data FD includes three-dimensional object modeling layer data BD and support part modeling layer data SD. The halftone processing unit 95 determines the voxel that forms the dot DT in the support unit SP0 based on the input value V2 that represents the dot formation rate (formation rate of the dot DT) in the voxel Vx included in the support unit SP0. . The storage unit 94 includes a nonvolatile memory and a RAM (Random Access Memory). The non-volatile memory stores a control program PR2 of the host device 9, a driver program of the modeling processing device 1, an application program such as CAD (Computer Aided Design) software, a dither matrix (example of dither mask) DZ, and the like. As the nonvolatile memory, a rewritable nonvolatile semiconductor memory such as a ROM (Read Only Memory) and a flash memory, a rewritable nonvolatile magnetic memory such as a hard disk, and the like can be used. The host device 9 includes a computer such as a personal computer.

The model data Dat is data indicating the shape and color of the model representing the three-dimensional object Obj, and is data for designating the shape and color of the three-dimensional object Obj. It should be noted that the color of the three-dimensional object Obj is the manner in which the plurality of colors are added when the three-dimensional object Obj is provided with a plurality of colors, that is, the pattern, characters, etc. represented by the plurality of colors attached to the three-dimensional object Obj. These images are also included. The model data Dat only needs to include information that can identify at least the external shape of the three-dimensional object Obj, and specifies the internal shape and material of the three-dimensional object Obj in addition to the external shape and color of the three-dimensional object Obj. It may be. As the data format of the model data Dat, AMF (Additive Manufacturing File Format), STL (Standard Triangulated Language), or the like can be used. The strength index value ST is a value for designating a strength necessary for supporting a portion (for example, the overhang portion OB2) to be supported by the support portion SP0 in the three-dimensional object Obj. The intensity index value ST may be, for example, “1” when a relatively weak intensity is sufficient, “2” when a higher intensity is necessary, “3” when a stronger intensity is necessary, and the like. .
The model data generation unit 92 is realized by, for example, a CAD application, and designates the shape and color of the three-dimensional object Obj based on information input by the user of the three-dimensional object modeling apparatus 100 by operating the display operation unit 91. The model data Dat and the intensity index value ST are generated as necessary.

  In this specific example, a method of modeling the three-dimensional object Obj and the support part SP0 in which the modeling layer LY is formed as a Q layer (Q is a natural number satisfying Q ≧ 2) will be described. In addition, the modeling layer LY formed by the q-th stacking process (q is a natural number satisfying 1 ≦ q ≦ Q) among the Q stacking processes for forming the modeling layer LY and the support part SP0 is the modeling layer LY [q]. The modeling layer data FD that defines the shape and color of the modeling layer LY [q] is referred to as modeling layer data FD [q].

  First, when the solid object Obj represented by the model data Dat has an overhang portion OB2 (an example of a portion supported by the support portion), the modeling data generation unit 93 selects the support portion SP0 that supports the overhang portion OB2. The support part modeling layer original data OD complemented under the overhang part OB2 is generated based on the strength index value ST. In addition, let the part which is not overhang part OB2 among the solid objects Obj be the main-body part OB1. Next, the modeling data generation unit 93 generates cross-sectional shape data indicating the shape and color of the cross-section obtained by slicing the three-dimensional shape indicated by the model data Dat and the support unit modeling layer source data OD for each thickness ΔZ. To do. In addition, the halftone processing unit 95 determines and determines the arrangement of dots to be formed by the modeling processing apparatus 1 in order to form the modeling layer LY [q] corresponding to the shape and color indicated by the cross-sectional shape data. The result is output as modeling layer data FD [q]. The modeling layer data FD [q] designates the dots DT to be formed in each voxel Vx by subdividing the shape and color indicated by the cross-sectional shape data into voxels (unit modeling bodies) Vx arranged in a grid pattern. The voxel Vx is a virtual solid, and in this specific example, the thickness is ΔZ and is a rectangular parallelepiped having a unit volume. Of course, the shape of the virtual voxel is not limited to a rectangular parallelepiped. Only one dot may be formed in one voxel Vx, or two or more dots may be formed.

  In order to model the three-dimensional object Obj, it is preferable that the three-dimensional object Obj is solid. When the shape specified by the model data Dat is a hollow shape, the modeling data generation unit 93 according to this specific example complements the hollow portion of the shape indicated by the model data Dat so that the three-dimensional object Obj is solid. Assume that data FD is generated. Alternatively, the hollow portion may be formed of a material that can be easily removed after three-dimensional modeling, such as water-soluble ink, and the material may be removed.

  The modeling processing apparatus 1 performs a lamination process of the modeling layer LY [q] based on the modeling layer data FD [q]. FIG. 2 shows an example in which the modeling layer LY [1] is formed based on the modeling layer data FD [1], and the modeling layer LY [2] is stacked based on the modeling layer data FD [2]. The modeling processing apparatus 1 models the three-dimensional object Obj and the support part SP0 by sequentially stacking the modeling layers LY [q].

  The modeling processing apparatus 1 shown in FIGS. 1 and 3 includes a modeling table 45, a carriage 41, a head unit (an example of a dot forming unit) 3, a curing unit 61, a position change mechanism 7, a storage unit 60, a processing control unit 6, and the like. Prepare. The modeling table 45 has a stacking surface of the modeling layer LY on the upper surface, and is installed so as to be movable up and down with respect to the housing 40 by the modeling table lifting mechanism 79a. The carriage 41 has the head unit 3 and an ink cartridge (an example of a liquid cartridge) 48 mounted thereon, and is disposed above the modeling table 45. As will be described in detail later, the head unit 3 has a recording head 30 having a plurality of ejection portions D that eject (spray) droplets (liquid LQ) toward the modeling table 45, and a drive signal to each ejection portion D. A drive signal generation unit 31 that generates Vin is provided. The modeling processing device 1 and the host device 9 excluding the head unit 3 are examples of the control unit U1.

  The curing unit 61 cures the dot DT by the liquid LQ discharged onto the modeling table 45. For the curing unit 61, a light source having a suitable wavelength or a heat source is used to cure the liquid LQ. For example, if ultraviolet curable ink is used as the liquid LQ, the curing unit 61 is constituted by an ultraviolet light source having a wavelength with good curing efficiency of the liquid LQ (for example, a near ultraviolet LED light source having a wavelength of 395 nm as a central wavelength). If a visible light curable ink is used as the liquid LQ, a visible light source is used for the curing unit 61, and if a thermosetting ink is used, a heat source such as an infrared heater is used for the curing unit 61. The curing unit 61 can be installed on the upper side (+ Z direction) of the modeling table 45, for example.

  The position change mechanism 7 includes drive motors 71 to 74, motor drivers 75 to 78, and the like. The lifting mechanism drive motor 71 is driven by a motor driver 75 and moves the modeling table 45 in the Z direction (+ Z direction and −Z direction) via the modeling table lifting mechanism 79a. The carriage drive motor 72 is driven by a motor driver 76 to move the carriage 41 in the Y direction (+ Y direction and −Y direction) along the carriage guide 79b. The carriage guide drive motor 73 is driven by a motor driver 77 to move the carriage guide 79b in the X direction (+ X direction and −X direction) along the guide 79c. The curing unit drive motor 74 is driven by a motor driver 78 to move the curing unit 61 in the X direction (+ X direction and −X direction) along the guide 79d.

  The storage unit 60 includes a nonvolatile memory and a RAM. The non-volatile memory stores a control program PR1 of the modeling processing apparatus. As the nonvolatile memory, a rewritable nonvolatile semiconductor memory such as a ROM and a flash memory, a rewritable nonvolatile magnetic memory such as a hard disk, and the like can be used. The RAM stores a control program PR1 developed from a non-volatile memory, modeling layer data FD from the host device 9, and the like. The control program PR1 stored in the storage unit 60 of the modeling processing device 1 and the control program PR2 stored in the storage unit 94 of the host device 9 are examples of the control program PR0.

  The processing control unit 6 includes a CPU that performs control processing of the entire modeling processing apparatus in accordance with the control program PR1 and the like. The processing control unit 6 controls the operations of the head unit 3 and the position change mechanism 7 based on the modeling layer data FD from the host device 9, so that the three-dimensional data corresponding to the model data Dat and the support unit modeling layer source data OD is obtained. The object Obj and the support part SP0 are modeled. For example, the processing control unit 6 generates various signals including an analog drive waveform signal Com and a waveform designation signal SI for driving the ejection unit D according to the modeling layer data FD, and outputs the generated signals to the head unit 3. To do. Further, the processing control unit 6 generates various signals for controlling the operations of the motor drivers 75 to 78 in accordance with the modeling layer data FD, and outputs these generated signals to the position change mechanism 7.

  FIG. 4 schematically shows an arrangement example of the nozzles NZ (a part of the ejection part D shown in FIG. 1) of the recording head 30 included in the head unit 3. 4 shows a nozzle surface 33 in which a plurality of nozzle rows 32 are arranged in the Y direction (scanning direction D1) in the recording head 30. FIG. The recording head 30 shown in FIG. 4 ejects the liquid LQ for forming dots from the nozzle NZ while moving in the scanning direction D1 (forward direction D2 and backward direction D3) with respect to the modeling table 45 that has not moved. It is assumed that bidirectional recording is performed. Of course, the present technology can also be applied to a recording head that performs unidirectional recording. The plurality of nozzle rows 32 include nozzle rows 32C, 32M, 32Y, 32W, 32CL, which are rows of first nozzles NZ1 that discharge droplets of modeling ink (example of modeling liquid) LQ1, and support ink ( Example of supporting liquid) It includes a nozzle row 32SP that is a row of second nozzles NZ2 that discharges droplets of LQ2. Here, in the nozzle row 32C, the first nozzles NZ1 that discharge C (cyan) droplets are arranged in the X direction. In the nozzle row 32M, the first nozzles NZ1 that discharge M (magenta) droplets are arranged in the X direction. In the nozzle row 32Y, the first nozzles NZ1 that discharge Y (yellow) droplets are arranged in the X direction. In the nozzle row 32W, the first nozzles NZ1 that discharge W (white) droplets are arranged in the X direction. In the nozzle row 32CL, the first nozzles NZ1 that discharge CL (clear) droplets are arranged in the X direction. In the nozzle row 32SP, the second nozzles NZ2 that discharge droplets of the supporting ink LQ2 are arranged in the X direction. Further, as shown in the lower side of FIG. 4, the first dot DT1 is formed from the droplet of the modeling ink LQ1, and the second dot DT2 is formed from the droplet of the supporting ink LQ2. The liquids (LQ1, LQ2) are collectively referred to as the liquid LQ, the nozzles NZ1, NZ2 are collectively referred to as the nozzle NZ, and the dots DT1, DT2 are collectively referred to as the dot DT.

  The C ink, M ink, and Y ink included in the modeling ink LQ1 are chromatic inks. The W ink contained in the modeling ink LQ1 is 30% or more (preferably 50%) of the irradiated light when irradiated with light having a wavelength belonging to the wavelength region of visible light (generally 400 to 700 nm). This is the achromatic ink that reflects the above light. The CL ink contained in the modeling ink LQ1 is an ink to which no color material is added, and is an ink having a low content of color material components and high transparency compared to the chromatic color ink and the achromatic color ink. The support ink LQ2 is preferably a water-soluble ink, an ink having a melting point lower than that of the modeling ink, or the like from the viewpoint of easily removing the support portion SP0, and a CL ink, a W ink, or the like can also be used.

The arrangement of the nozzles NZ in each nozzle row 32 may be a direction shifted from the X direction in the nozzle surface 33, and may be not only linear but also so-called staggered.
In addition to the nozzle NZ, the ejection unit D shown in FIG. 1 has a drive element that ejects liquid droplets from the nozzle NZ by an applied drive signal Vin. As the driving element, a piezoelectric element that applies pressure to the liquid LQ in the pressure chamber communicating with the nozzle NZ, a thermal element that generates bubbles in the pressure chamber by heat and discharges droplets from the nozzle NZ, and the like can be used. In this embodiment, the drive element is configured by using a piezoelectric element as a piezoelectric element. Liquid LQ is supplied from the ink cartridge 48 to the pressure chamber. The liquid LQ in the pressure chamber is ejected as a droplet from the nozzle NZ toward the modeling table 45 by the driving element, and droplet dots DT are formed on the modeling layer LY. By the relative movement of the recording head 30 and the modeling table 45, the modeling layer LY corresponding to the modeling layer data FD is formed.

  Various known circuits that apply a drive signal to a drive element that discharges droplets from the nozzle NZ can be used for the drive signal generation unit 31.

FIG. 5 schematically shows an example of a concept for generating the discharge of droplets for forming dots or the non-discharge of droplets from the drive signal Vin. Note that the waveform PL1 of the drive signal Vin shown in FIG. 5 is merely schematic and is not necessarily an actual waveform.
In this example, when ejecting droplets for dot formation from the nozzle NZ, the drive signal generation unit 31 drives the waveform PL1 in a predetermined ejection unit period Tu based on the drive waveform signal Com input from the processing control unit 6. The signal Vin is supplied to the discharge unit D. Thereby, a droplet is ejected from the nozzle NZ at a timing according to the waveform PL1, and a dot is formed. Further, when the droplets are not ejected from the nozzle NZ, the drive signal generation unit 31 does not supply the waveform PL1 to the ejection unit D. Thereby, a droplet is not discharged from the nozzle NZ and a dot is not formed.

(3) First processing example of the three-dimensional object forming apparatus:
FIG. 6 shows an example of a modeling process performed by the three-dimensional object modeling apparatus 100 shown in FIG. This processing is performed in cooperation by the modeling data generation unit 93 of the host device 9 and the processing control unit 6 of the modeling processing device 1. When the modeling data generation unit 93 acquires at least the model data Dat from the model data generation unit 92, the modeling data generation unit 93 performs a modeling layer data generation process in steps S102 to S106. Hereinafter, the description of “step” is omitted. The host device 9 executes a plurality of processes in parallel by multitasking. When the processing control unit 6 acquires the modeling layer data FD from the host device 9, the processing control unit 6 controls the modeling of the three-dimensional object Obj and the support SP0 by the dots DT that are cured in the modeling processing of S108 to S114. The modeling processing apparatus 1 executes a plurality of processes in parallel by multitasking.
FIG. 7 schematically shows how the modeling layer data FD including the three-dimensional object modeling layer data BD and the support unit modeling layer data SD is generated from the model data Dat. The lower part of FIG. 7 schematically shows modeling layer data FD representing the three-dimensional object Obj supplemented with the support part SP0.

  The modeling data generation unit 93 that has acquired the model data Dat and the intensity index value ST as necessary first generates, in the halftone processing unit 95, the three-dimensional object modeling layer data BD based on the cross-sectional shape data of the three-dimensional object Obj. (S102). For example, it is assumed that the cross-sectional shape data is multi-gradation data (for example, 256 gradations) representing the three-dimensional object Obj by a Q-layered modeling layer LY [q] (q = 1, 2,..., Q). In this case, Q layer three-dimensional object modeling layer data BD [q] representing the formation status of the dots DT may be generated by performing halftone processing on the cross-sectional shape data. The halftone process may be a systematic dither method halftone process using a dither matrix (an example of a dither mask) DZ1. Whether the three-dimensional object formation layer data BD [q] forms a dot DT (for example, 1) or not (for example, 0) for each of C ink, M ink, Y ink, W ink, and CL ink, for example. Can be binary data. When the three-dimensional object Obj has a solid structure, the three-dimensional object modeling layer data BD [q] forms dots DT of C ink, M ink, Y ink, W ink, or CL ink in all voxels Vx (for example, 1) It becomes binary data.

  After the generation of the three-dimensional object formation layer data BD, the formation data generation unit 93 generates the support part formation layer original data OD based on the strength index value ST (S104). For example, when the support part modeling layer original data OD is multi-gradation data (for example, 256 gradations), the support part modeling layer source data OD of the portion whose strength index value ST is “1” (relatively low strength). Is "32", the strength index value ST is "2" (medium strength), the support portion modeling layer original data OD is "64", and the strength index value ST is "3" (relatively high strength) It is good also considering the support part modeling layer original data OD of a certain part as "128". When the support part modeling layer source data OD represents the support part SP0 as a Q layer modeling layer LY [q], the Q layer support part modeling layer source data OD [q] is generated from the strength index value ST. Also good. The support portion modeling layer original data OD becomes the input value V2 of the halftone process in S106.

After the generation of the support unit modeling layer source data OD, the modeling data generation unit 93 performs a halftone process on the input value V2 of each voxel Vx of the support unit modeling layer source data OD in the halftone processing unit 95. The support part modeling layer data SD representing the formation status of the dots DT is generated (S106). For example, the input value V2 (for example, 256 gradations) of the multi-gradation (for example, 256 gradations) in which the support part modeling layer source data OD represents the support part SP0 as a Q layer of modeling layers LY [q] (q = 1, 2,..., Q). It is assumed that the support portion modeling layer source data OD [q] has x, y) in each voxel Vx. In this case, the support layer modeling layer data SD [q] of the Q layer representing the formation state of the dots DT may be generated by performing halftone processing on each input value V2 (x, y). Here, x represents a coordinate value in the X direction, and y represents a coordinate value in the Y direction. The halftone process may be a systematic dither method halftone process using a dither matrix (an example of a dither mask) DZ2. In this processing example, the dither matrix DZ2 is used for the support portion halftone processing in S106. The support portion modeling layer data SD [q] can be, for example, binary data indicating whether the dot DT is formed (for example, 1) or not (for example, 0) for the support ink LQ2. The support modeling layer data SD [q] may include binary data that does not form the dots of the support ink LQ2 in the voxel Vx (for example, 0).
Details of the support portion halftone process in S206 will be described later.

  The modeling data generation unit 93 transmits the modeling layer data FD including the three-dimensional object modeling layer data BD and the support unit modeling layer data SD to the modeling processing device 1. The modeling processing apparatus 1 receives the modeling layer data FD. The process control unit 6 that has acquired the modeling layer data FD first sets the modeling layer LY [q] for forming the dots DT (S108). This process can be, for example, a process of setting the number of processes (1, 2,..., Q) in S108 to a variable q indicating the number of executions of the stacking process. The same applies to the following. Next, the processing control unit 6 causes the motor driver 75 to drive the lifting mechanism drive motor 71 so as to move the modeling table 45 to a position in the Z direction for forming the modeling layer LY [q] (S110). For example, when forming the modeling layer LY [1] of FIG. 2, the process control unit 6 raises the modeling table 45 to a predetermined proximity position close to the curing unit 61. When forming the modeling layer LY [2] in FIG. 2, the processing control unit 6 lowers the modeling table 45 by a thickness ΔZ from the proximity position.

  After the modeling table 45 is moved, the processing control unit 6 causes the head unit 3, the position change mechanism 7, and the molding unit LY [q] to be formed based on the qth modeling layer data FD [q]. Then, the operation of the curing unit 61 is controlled (S112). For example, this process may be a process of repeatedly ejecting ink droplets (liquid LQ) from the nozzle NZ and feeding the head unit 3 in the X direction while scanning the head unit 3 in the scanning direction D1 (Y direction). it can. For example, the process control unit 6 causes the motor driver 76 to drive the carriage drive motor 72 so as to move the head unit 3 in the scanning direction D1. Further, the process control unit 6 causes the motor driver 77 to drive the carriage guide drive motor 73 so as to move the carriage guide 79b in the X direction together with the head unit 3. Here, the modeling ink LQ1 is ejected from the first nozzle NZ1 according to the three-dimensional object modeling layer data BD [q] to form the first dots DT1 of a predetermined size. Further, the support nozzle LQ2 is ejected from the second nozzle NZ2 in accordance with the support portion modeling layer data SD [q], thereby forming a second dot DT2 having a predetermined size.

  The dots DT1 and DT2 that have passed the head unit 3 on the upper side are irradiated with ultraviolet rays (UV) from the curing unit 61 from above. Thereby, the components contained in the inks LQ1, LQ2 are polymerized, and the dots DT1, DT2 are cured. In this way, the modeling layer LY [q] is formed by the dots DT1 and DT2 that are cured.

  After forming the modeling layer LY [q], the processing control unit 6 determines whether or not all the modeling layers LY [q] are set (S114). When q <Q, the process control unit 6 repeats the processes of S108 to S114. For example, when q = 1, the modeling layer LY [2] is set in the next process of S108. When q = Q, the process control unit 6 ends the modeling process. As a result, the three-dimensional object Obj and the support part SP0 are placed on the modeling table 45.

FIG. 8 schematically shows an example of the structure of the dither mask. A dither matrix DZ2 shown in FIG. 8 is an example of a dither matrix DZ that can be used for the support halftone processing of S106. The dither matrix DZ2 has 10 × 10 thresholds, but the number of thresholds in the dither matrix may be 11 × 11 or more, or 9 × 9 or less. The shape of the dither mask is not limited to a square shape, and may be a rectangular shape.
Each cell (square square) shown in FIG. 8 represents a storage element E1 of the dither matrix DZ, and a numerical value assigned to each cell represents a threshold value T (x, y) stored in the storage element E1. In the dither matrix DZ shown in FIG. 8, when the arrangement of the dots DT is determined using the dither matrix DZ, the first direction in which the probability that two dots are formed adjacent to each other is the highest is expected. W1 is defined. For easy understanding, the input value V2 (x, y) of the support portion modeling layer original data OD is expressed by an integer of 0 to 100 corresponding to a percentage, and each threshold value of the dither matrix DZ is different from each other. It shall be determined to be. When the input value V2 is a gradation value of 0 to 255, a dot formation rate of 50% corresponds to a gradation value of about 128, and a dot formation rate of 25% corresponds to a gradation value of about 64.

  In FIG. 8, when the input value V2 (x, y) is a dot formation rate of 20%, the storage element in which the dot DT is formed is surrounded by a bold line. One or more columns K0 (support structure ST0) for supporting the three-dimensional object Obj are formed by the dots DT formed on the support part SP0.

  When the modeling layer LY [q] of the support part SP0 is larger than the dither matrix DZ2, by arranging a plurality of dither matrices DZ2, all the input values V2 (x, y) of the support part modeling layer original data OD are set in the dither matrix DZ2. It can be associated with a threshold value. For example, as shown in FIG. 9, when the number of voxels in the modeling layer LY [q] of the support portion SP0 in the X direction is larger than the number of storage elements 10 in the dither matrix DZ2, the dither matrix DZ2 is arranged in the X direction. . Further, when the number of voxels of the modeling layer LY [q] of the support portion SP0 in the Y direction is larger than the number of storage elements 10 of the dither matrix DZ2, the dither matrix DZ2 is arranged in the Y direction. In FIG. 9, the modeling layer LY [q] of the support part SP0 is 2.5 times the number of storage elements of the dither matrix DZ2 in the X direction and 1.5 times the number of storage elements of the dither matrix DZ2 in the Y direction. The case where it is is shown typically. In this case, three dither matrices DZ2 are arranged in the X direction and two are arranged in the Y direction.

  FIG. 10 schematically shows an example of the support structure ST0 formed in the support part SP0 without the three-dimensional object Obj. In the support portion halftone process of this specific example, the dots DT are arranged in the voxel set of the support portion SP0 so that one or more columns K0 extending in the Z direction are formed as the support structure ST0. In FIG. 10, the symbol W1 indicates a first direction that is relatively long in the cross section of the column K0, and the symbol W2 indicates a second direction that is orthogonal (crossed) to the first direction W1. FIG. 10 shows an example in which eight columns K1 to K8 (examples of columns K0) are formed on the support part SP0.

Here, the number of columns K0 whose length in the first direction W1 is longer than the length in the second direction W2 in the cross section is NW1, and in the cross section, the length in the second direction W2 is longer than the length in the first direction W1. The number of K0 is NW2. In the support halftone processing of this specific example, the dots DT are arranged in the voxel set of the support SP0 so that NW1> NW2. FIG. 10 shows an example where NW1 = 8 and NW2 = 0. In order to satisfy NW1> NW2, the dither matrix DZ2 shown in FIG. 8 has the number NW1 of pillars in which the length in the first direction W1 is longer than the length in the second direction W2, and the length in the second direction W2 is the first direction W1. It has the directivity which makes more than the number NW2 of support | pillars longer than the length of.
Note that the threshold of the dither matrix DZ1 (see FIG. 6) for generating the three-dimensional object formation layer data BD by halftone processing can be the same as that of the dither matrix DZ2, but the dispersibility of the dots DT is increased. An important arrangement is preferred. In the case where the threshold value of the dither matrix DZ1 is arranged with an emphasis on dispersibility, the threshold value of the dither matrix DZ2 for the support portion having directivity is different from that of the dither matrix DZ1 for the three-dimensional object.

The cross-sectional shape of the column K0 may be a shape that does not change in the Z direction as shown in FIG. 10, or a shape that changes in the Z direction as shown in FIG. FIG. 11 schematically shows an example in which the dot DT density of the second part SP2 closer to the overhang part OB2 than the first part SP1 in the support structure ST0 is lowered. In this specific example, since the dots DT can be arranged on the support SP0 by the support halftone process, it is easy to change the density of the dots DT depending on the position.
Hereinafter, a specific example of the support portion halftone process using the dither matrix DZ2 in S106 of FIG. 6 will be described.

FIG. 12 shows a specific example of the systematic dither method of the support halftone processing performed by the halftone processing unit 95 in S106 of FIG.
When the process is started, the halftone processing unit 95 sets the modeling layer LY [q] to be subjected to the halftone process (S202). Next, the halftone processing unit 95 sets a processing target voxel position (x, y) from all the voxel positions included in the modeling layer LY [q] of the support part SP0 (S204). For example, as shown in the upper right of FIG. 12, the voxel positions are set in the order of x = 1, 2,..., Xmax when y = 1, and the voxel positions are set in the order of x = 1, 2,. It may be set and such repetition may be performed in the order of y = 1, 2,..., Ymax. In the example shown in FIG. 12, one unset voxel position (x, y) is set from among the Xmax × Ymax voxel positions. Of course, the setting order of the voxel positions is not limited to the example shown in FIG.

  After setting the voxel position, the halftone processing unit 95 acquires the threshold value T (x, y) corresponding to the set voxel position (x, y) from the dither matrix DZ2 (S206). When the modeling layer LY [q] of the support part SP0 is larger than the dither matrix DZ2, the threshold value T (x) corresponding to the set voxel position (x, y) after arranging a plurality of dither matrices DZ2 as shown in FIG. , Y) may be read from the dither matrix DZ2. In the example shown in FIG. 9, the set voxel position (from the upper right dither matrix DZ21 overlapping the set voxel position (x, y) of the modeling layer LY [q] of 25 voxels in the X direction and 15 voxels in the Y direction ( The threshold value T (x, y) corresponding to x, y) is acquired.

After acquiring the threshold value T (x, y), the halftone processing unit 95 uses the input value V2 (x, y) corresponding to the set voxel position (x, y) as the support unit modeling layer original data OD [q]. From this, it is determined whether or not the input value V2 (x, y) is equal to or greater than the threshold value T (x, y) (S208). When V2 (x, y) ≧ T (x, y), the halftone processing unit 95 represents data indicating that there is a dot at the set voxel position (x, y) of the support forming layer data SD [q] (for example, 1) is stored (S210). When V2 (x, y) <T (x, y), the halftone processing unit 95 represents data indicating that there is a dot at the set voxel position (x, y) of the support forming layer data SD [q] (for example, 0) is stored (S212).
For example, it is assumed that an input value V2 corresponding to a dot formation rate of 20% is stored in each voxel of the support part modeling layer original data OD [q]. When the dither matrix DZ2 shown in FIG. 8 is used, the support portion modeling layer data SD [q] at the voxel position where the threshold T (x, y) is 20 or less becomes “1” indicating that there is a dot, and the threshold T ( The support forming layer data SD [q] at the voxel position where x, y) is greater than 20 is “0” indicating no dot.

After the binary data is stored in the set voxel position (x, y) of the support part modeling layer data SD [q], the halftone processing unit 95 determines whether all the voxel positions have been set (S214). When the unset voxel position remains, the halftone processing unit 95 repeats the processes of S204 to S214. When all the voxel positions are set, the halftone processing unit 95 determines whether all the modeling layers LY [q] are set (S216). When q <Q, the halftone processing unit 95 repeats the processes of S202 to S216. When q = Q, the halftone processing unit 95 ends the support unit halftone process. Then, the process of S108-S114 of FIG. 6 is performed, and it will be in the state by which the solid object Obj and support part SP0 in which modeling layer LY [q] were laminated | stacked in order are mounted on the modeling stand 45. FIG.
With the above processing, the halftone processing for forming the dot DT in the support portion SP0 based on the input value V2 representing the dot formation rate in the voxel Vx included in the voxel set representing the support portion SP0 and the dither matrix DZ is performed. Done. Accordingly, the dots DT are arranged in the voxel set of the support part SP0 so that the support structure ST0 that supports the three-dimensional object Obj is formed.

For example, when the input value V2 of each support part modeling layer original data OD [q] is the same value, the same threshold value T (x, y) is used from the dither matrix DZ2 if the voxel position (x, y) is the same. Is done. Since the obtained support part modeling layer data SD [q] is the same, the dots DT are continuously formed in the Z direction at the voxel positions where the dots DT are formed, and the Z directions are at the voxel positions where the dots are not formed. No dots are formed continuously. As a result, as shown in FIG. 10, one or more columns K0 extending in the Z direction are formed on the support portion SP0 as the support structure ST0.
Further, in the dither matrix DZ2, the number NW1 of pillars whose length in the first direction W1 is longer than the length in the second direction W2, and the number NW2 of pillars whose length in the second direction W2 is longer than the length in the first direction W1. It has the directivity to make more. Thereby, in the modeling layer LY in the support part SP0, the halftone process in which the dots DT are easily connected to the first direction W1 relative to the input value V2 as compared to the second direction W2 is performed.

As described above, the halftone processing unit 95 is based on the input value V2 representing the dot formation rate in the voxel Vx included in the voxel set representing the support unit SP0 and the dither matrix DZ2 in the support unit SP0. The dots DT are arranged in the voxel set so that the support structure ST0 that supports the three-dimensional object Obj is formed. For example, when the input value V2 is changed so as to increase the dot formation rate, the density of the dots DT of the support structure ST0 increases. When the input value V2 is changed so as to reduce the dot formation rate, the density of the dots DT of the support structure ST0 decreases. Therefore, the present specific example can provide a technique capable of easily controlling the density of the support portion of the three-dimensional object.
In addition, as shown in FIG. 10, the number NW1 of pillars in which the length in the first direction W1 is longer than the length in the second direction W2 in the cross section, the length in the second direction W2 is longer than the length in the first direction W1. Since the number of long supports NW2 can be increased, the strength of the support structure ST0 in the first direction W1 is higher than the strength of the support structure ST0 in the second direction W2. Therefore, the present specific example can save the material (supporting ink LQ2) for forming the three-dimensional object support structure, and provide a technique capable of efficiently ensuring the strength of the three-dimensional object support structure. it can.

(4) Second processing example of the three-dimensional object forming apparatus:
By the way, the direction in which priority is given to securing the strength of the support part SP0 on the XY plane along the modeling layer LY varies depending on the shape of the three-dimensional object Obj. Therefore, as shown in FIG. 13 and the like, it is preferable that the first direction W1 that is relatively long in the cross section of the column K0 can be directed to the setting direction DS1 in which priority is given to securing the strength of the support portion SP0.

  FIG. 13 shows an example of processing for selecting the dither matrix DZ according to the setting direction DS1. In this processing example, a plurality of dither matrices DZ11 to DZ14 having different directions with the highest strength of the support structure ST0 of the three-dimensional object Obj are used. These dither matrices DZ11 to DZ14 are included in the support portion dither matrix DZ2. Here, the dither matrix DZ11 in the high intensity direction 0 ° is a dither matrix in which the first direction W1 in which the dots DT are easily connected on the XY plane along the modeling layer LY and the strength is high is 0 ° (X direction). The threshold value of the dither matrix DZ11 can be, for example, an arrangement obtained by rotating the arrangement of the threshold value shown in FIG. 8 by 90 °. In the dither matrix DZ12 having a high intensity direction of 45 °, the first direction W1 in which the dots DT are easily connected on the XY plane along the modeling layer LY and the strength is high is 45 ° (the direction shifted by 45 ° from the + X direction to the + Y direction). A dither matrix is used. The dither matrix DZ13 having a high intensity direction of 90 ° is a dither matrix having a first direction W1 of 90 ° (Y direction) in which the dots DT are easily connected on the XY plane along the modeling layer LY and the strength is high. The threshold value of the dither matrix DZ13 can be the threshold value arrangement shown in FIG. 8, for example. In the dither matrix DZ14 of 135 ° in the high intensity direction, the first direction W1 in which the dots DT are easily connected to the XY plane along the modeling layer LY and the strength is high is 135 ° (the direction deviated by 45 ° from the + Y direction to the −X direction). The dither matrix.

  13 is performed between S104 and S106 of the modeling process shown in FIG. After the generation of the support part modeling layer original data OD in S104, the halftone processing part 95 receives the setting direction DS1 giving priority to securing the strength of the support part SP0 from the display operation part 91 (S122). The setting direction DS1 is a direction in which priority is given to the connection of the dots DT. In the setting process shown in FIG. 13, the setting direction DS1 is set from 0 °, 45 °, 90 °, and 135 °. After receiving the setting direction DS1, the halftone processing unit 95 selects a dither matrix that matches the setting direction DS1 from the dither matrices DZ11 to DZ14 (S124). For example, when 90 ° (Y direction) is accepted as the setting direction DS1, the dither matrix DZ13 of 90 ° in the high intensity direction is selected. Thereafter, the halftone processing unit 95 performs the support unit halftone processing of S106 of FIG. 6 using the selected dither matrix.

Through the above processing, in the modeling layer LY in the support part SP0, the dot DT is set in the setting direction DS1 compared to the input value V2 in the direction (second direction W2) orthogonal to the setting direction DS1 (first direction W1). Halftone processing that is easy to connect is performed. As a result, the number NW1 of struts whose length in the setting direction DS1 is longer than the length in the orthogonal direction (W2) in the cross section is smaller than the number NW2 of columns whose length in the orthogonal direction (W2) is longer than the length in the setting direction DS1. Since it can be increased, the strength of the support structure ST0 in the setting direction DS1 is higher than the strength of the support structure ST0 in the orthogonal direction (W2). As described above, this specific example can control the formation of the support structure in accordance with a direction in which priority is given to securing the strength, and can provide a technique capable of efficiently securing the strength of the three-dimensional support structure.
Of course, the dither matrix prepared for each direction in which priority is given to securing the strength of the support part SP0 may be two or three, or may be five or more.

(5) Third processing example of the three-dimensional object forming apparatus:
If a dither matrix is prepared for each angle where priority is given to securing the strength of the support part SP0, the data capacity for storing the dither matrix increases. Therefore, as shown in FIG. 14, the dither matrix may be rotated and used as necessary.

  FIG. 14 shows an example in which the dither matrix DZ is rotated in the support portion halftone preprocessing. In this example, a dither matrix DZ11 with a high intensity direction of 0 ° and a dither matrix DZ12 with a high intensity direction of 45 ° are prepared, and a dither matrix DZ13 with a high intensity direction of 90 ° or a dither matrix with a high intensity direction of 135 ° is prepared as necessary. The matrix DZ14 is generated. The number of storage elements of the dither matrices DZ11 to DZ14 is the same in the X direction and the Y direction, and the dither matrix is rotated in units of 90 °. The threshold value of the dither matrix DZ13 in the high intensity direction 90 ° is arranged by rotating the threshold value of the dither matrix DZ11 in the high intensity direction 0 ° by 90 °. The threshold value of the dither matrix DZ14 in the high intensity direction 135 ° is set to be an arrangement obtained by rotating the threshold value of the dither matrix DZ12 in the high intensity direction 45 ° by 90 °.

  14 is also performed between S104 and S106 in the modeling process shown in FIG. After the generation of the support part modeling layer original data OD in S104, the halftone processing part 95 receives the setting direction DS1 giving priority to securing the strength of the support part SP0 from the display operation part 91 (S122). In the setting process shown in FIG. 14, the setting direction DS1 is set from 0 °, 45 °, 90 °, and 135 °. After receiving the setting direction DS1, the halftone processing unit 95 selects a dither matrix to be used from the dither matrices DZ11 and DZ12 (S124). In this example, the dither matrix DZ11 is selected when the setting direction DS1 is 0 ° or 90 °, and the dither matrix DZ12 is selected when the setting direction DS1 is 45 ° or 130 °. After selecting the dither matrix, the halftone processing unit 95 determines whether the dither matrix needs to be rotated in order to use the dither matrix that matches the setting direction DS1 (S126). For example, when 90 ° or 135 ° is selected as the setting direction DS1, it is necessary to rotate the dither matrix. In this case, the halftone processing unit 95 performs dither matrix rotation processing (S128). Here, each threshold value of the dither matrix before rotation is T0 (x, y), each threshold value of the dither matrix after rotation is T (x, y), and the number of storage elements in the X direction is Nx (stored in the Y direction). Same as the number of elements). In this case, for example, the threshold value T0 (Nx + 1−y, x) before rotation may be set as the threshold value T (x, y) after rotation. In this example, when the setting direction DS1 is 90 °, the dither matrix DZ11 of the high intensity direction 0 ° is rotated by 90 °, and when the setting direction DS1 is 135 °, the dither matrix DZ12 of the high intensity direction 45 ° is 90 °. ° Rotating. On the other hand, when 0 ° or 45 ° is selected as the setting direction DS1, the dither matrix is used as it is. Thereafter, the halftone processing unit 95 performs the support unit halftone processing of S106 of FIG. 6 using the rotated or selected dither matrix.

  Also by the above processing, in the modeling layer LY in the support portion SP0, the dot DT is set in the setting direction DS1 compared to the input value V2 in the direction (second direction W2) orthogonal to the setting direction DS1 (first direction W1). A halftone process is easily performed. Therefore, the present specific example can provide a technique capable of efficiently ensuring the strength of the support structure for the three-dimensional object, and can reduce the data capacity for storing the dither mask.

(6) Fourth processing example of the three-dimensional object forming apparatus:
Further, in order to reduce the data capacity for storing the dither matrix, as shown in FIGS. 15 and 16, the support part modeling layer original data OD and the support part modeling layer data SD may be rotated as necessary.

  FIG. 15 shows an example of an alternative process performed in place of S106 in the modeling process shown in FIG. In this example, only the dither matrix DZ11 of 0 ° in the high intensity direction is prepared, and the dither matrices DZ12 to DZ14 are not used. In the alternative process shown in FIG. 15, the support part modeling layer original data OD is rotated before the support part halftone process using the dither matrix DZ11, and the support part modeling layer data SD is rotated after the support part halftone process. We are going to do the processing. FIG. 16 schematically shows an example of performing rotation processing of data OD and SD before and after the support portion halftone processing.

  After the generation of the support part modeling layer original data OD in S104 of FIG. 6, the halftone processing part 95 receives from the display operation part 91 the setting direction DS1 in which the halftone processing part 95 gives priority to securing the strength of the support part SP0 ( S132). When rotating the support part modeling layer original data OD and the support part modeling layer data SD, since the degree of freedom of the rotation angle is high, even if the setting direction DS1 is received in a smaller unit compared to the examples shown in FIGS. Good.

After receiving the setting direction DS1, the halftone processing unit 95 sets the modeling layer LY [q] to be subjected to the halftone processing (S134). Next, the halftone processing unit 95 rotates the support unit modeling layer original data OD [q] in the 0 ° direction from the setting direction DS1 (S136). FIG. 16 schematically shows a state where the support portion modeling layer original data OD [q] is rotated by −θ by setting the angle of the setting direction DS1 to θ. If the non-circular support part modeling layer original data OD [q] is simply rotated, the presence or absence of dots cannot be determined for some voxels of the final support part modeling layer data SD [q]. Therefore, a plurality of support unit modeling layer source data OD [q] are arranged in the X direction and the Y direction to generate enlarged support unit modeling layer source data OD1 [q], and this enlarged support unit modeling layer source data OD1 [q] is − The rotation support part modeling layer original data OD2 [q] is generated by performing affine transformation for θ rotation. Here, the voxel position of the enlarged support part modeling layer original data OD1 [q] before rotation is (x0, y0), and the voxel position of the rotation support part modeling layer original data OD2 [q] after rotation is (x, y ), Affine transformation can be performed by the following equation.

After generating the rotation support unit modeling layer original data OD2 [q], the halftone processing unit 95 determines whether or not all the modeling layers LY [q] are set (S138). When q <Q, the halftone processing unit 95 repeats the processes of S134 to S138. When q = Q, the halftone processing unit 95 performs the support unit halftone process of FIG. 12 using the dither matrix DZ11 in the high intensity direction 0 °, and the rotation support unit modeling layer original data OD2 before the rotation. Support part modeling layer data SD1 is generated (S140). FIG. 16 schematically illustrates a state in which the dither matrix DZ11 is applied to the q-th rotation support part modeling layer original data OD2 [q] to generate the q-th pre-rotation support part modeling layer data SD1 [q]. It shows.
By the above process, the halftone process in which the dots DT are easily connected in the 0 ° direction (first direction W1) with respect to the input value V2 is performed in the modeling layer LY in the support part SP0.

After the generation of the support unit modeling layer data SD, the halftone processing unit 95 sets the modeling layer LY [q] to be subjected to the halftone process (S142). Next, the halftone processing unit 95 rotates the pre-rotation support unit modeling layer data SD1 [q] from the 0 ° direction in the setting direction DS1 (S144). FIG. 16 schematically shows a state in which the pre-rotation support portion modeling layer data SD1 [q] is rotated by θ. If the non-circular pre-rotation support portion modeling layer data SD1 [q] is simply rotated, the presence or absence of dots cannot be determined for some voxels of the final support portion modeling layer data SD [q]. Therefore, the affine transformation that makes the pre-rotation support part modeling layer data SD1 [q] larger than the final support part modeling layer data SD [q] and rotates the pre-rotation support part modeling layer data SD1 [q] by θ is performed. The rotation support part modeling layer data SD2 [q] is generated to cut out the final support part modeling layer data SD [q]. Here, when the voxel position of the support part modeling layer data SD1 [q] before rotation is (x, y) and the voxel position of the rotation support part modeling layer data SD2 [q] after rotation is (x0, y0), Affine transformation can be performed by the following equation.

After the final support part modeling layer data SD [q] is generated, the halftone processing unit 95 determines whether all the modeling layers LY [q] have been set (S146). When q <Q, the halftone processing unit 95 repeats the processes of S142 to S146. When q = Q, the halftone processing unit 95 ends the substitution process. Thereafter, the halftone processing unit 95 performs the processing of S108 to S114 in FIG.
Through the above process, the process obtained by rotating the data obtained by the halftone process so that the first direction W1 is directed to the setting direction DS1 that actually gives priority to the connection of the dots DT is performed, thereby forming the support structure ST0. As described above, the dots DT are arranged in the voxel set of the support part SP0.

  Also by the above processing, in the modeling layer LY in the support portion SP0, the dot DT is set in the setting direction DS1 compared to the input value V2 in the direction (second direction W2) orthogonal to the setting direction DS1 (first direction W1). A halftone process is easily performed. The setting direction DS1 can be set finely. Therefore, the present specific example can provide a technique capable of ensuring the strength of the three-dimensional support structure more efficiently.

(7) Fifth processing example of the three-dimensional object forming apparatus:
By the way, if the input value V2 of the support portion modeling layer original data OD is set using information on the overhang portion OB2 (the portion of the three-dimensional object Obj supported by the support portion SP0), the support structure ST0 having a desired density can be easily set. Can be formed on the support portion SP0.

  17 and 18 schematically show an example in which the density of the dots DT of the support portion SP0 is changed according to the weight of each location of the overhang portion OB2. The overhang portion OB2 shown in FIG. 17 includes a relatively heavy and heavy overhang portion OB21 and a relatively light and lightweight overhang portion OB22. The support portion SP01 below the weight overhang portion OB21 is formed with a column K11 in which the dots DT are made relatively thick with a relatively high density (for example, a dot formation rate of 50%). A support column SP02 below the lightweight overhang portion OB22 is formed with a column K12 in which the dots DT have a relatively low density (for example, a dot formation rate of 25%) and are relatively thin. Accordingly, the overhang portion OB2 can be efficiently supported by reducing the amount of the supporting ink LQ2 used under the light weight overhang portion OB22 while reliably supporting the heavy overhang portion OB21.

  In the case of the overhang portion OB2 shown in FIG. 18, the lower portion from the lower surface of the weight overhang portion OB21 in the support portion SP0 is the first portion SP1, and the upper portion from the lower surface of the weight overhang portion OB21 is the second portion SP2. . The first portion SP1 is provided with a column K11 in which the dots DT are made relatively thick with a relatively high density (for example, a dot formation rate of 50%). Thereby, the weight overhang part OB21 is supported by the comparatively thick support | pillar K11. Further, in the second part SP2, a support column K12 is formed in which the dots DT are relatively thin with a relatively low density (for example, a dot formation rate of 25%). Thereby, the light weight overhang part OB22 is supported by the comparatively thin support | pillar K12.

FIG. 19 shows a specific example of the support portion modeling layer original data generation processing performed by the halftone processing portion 95 in S104 of FIG.
When the process is started, the halftone processing unit 95 sets a processing target voxel position (x, y) from among all the voxel positions included in the modeling layer LY of the support part SP0 (S302). After setting the voxel position, the halftone processing unit 95 acquires the number N0 of voxels of the overhang portion OB2 at the set voxel position (x, y) from the three-dimensional object formation layer data BD (S304). The number of voxels N0 of the overhang portion OB2 corresponds to the height (length in the Z direction) of the overhang portion OB2 at the set voxel position (x, y), and the overhang portion OB2 at the set voxel position (x, y). Corresponds to the weight of.

  After obtaining the number of voxels N0 of the overhang portion OB2, the halftone processing unit 95 sets an intensity index value ST that specifies the strength necessary to support the overhang portion OB2 based on the number of voxels N0 (S306). . For example, as shown in FIG. 19, assuming that integer values N01, N02, and N03 satisfy 1 <N01 <N02 <N03, ST = 1 (relatively low intensity) and N01 ≦ N0 when 1 ≦ N0 <N01. When <N02, ST = 2 (medium strength), when N02 ≦ N0 <N03, ST = 3 (relatively high strength), and the like.

After setting the intensity index value ST, the halftone processing unit 95 determines whether all voxel positions have been set (S308). If there are remaining unset voxel positions, the halftone processing unit 95 repeats the processing of S302 to S308. When all the voxel positions are set, the halftone processing unit 95 generates support unit modeling layer original data OD [1], OD [2],... Based on the intensity index value ST and the model data Dat (S310). Then, the support part modeling layer original data generation process is terminated. For example, as shown in FIG. 19, the input value V2 (support portion modeling layer original data OD) of the portion where the strength index value ST is “1” (relatively low strength) is a value corresponding to a dot formation rate of 12.5%. (For example, gradation value 32), the input value V2 (supporting part forming layer original data OD) of the portion where the intensity index value ST is “2” (medium intensity) is a value equivalent to 25% (for example, gradation value 64). ), The input value V2 (supporting part forming layer original data OD) of the portion where the strength index value ST is “3” (relatively high strength) may be set to a value equivalent to 50% (for example, gradation value 128), and the like. .
Thereafter, the processing of S106 to S114 in FIG. 6 is performed, and the support SP0 having the dot formation rate corresponding to the three-dimensional object Obj and the input value V2 is formed.

With the above processing, the input value V2 is set so that the support structure ST0 having a density based on the information related to the overhang part OB2 is formed, and the dots DT are arranged in the voxel set of the support part SP0 according to this setting, and the desired value is set. A dense support structure ST0 is formed. Therefore, this example can provide a suitable technique for efficiently ensuring the strength of the three-dimensional object support structure.
Note that the information related to the overhang portion OB2 may include the area of the overhang portion OB2.

(8) Sixth processing example of the three-dimensional object forming apparatus:
Further, even if the input value V2 of the support portion modeling layer original data OD is set according to the position of the support portion SP0 in the Z direction (stacking direction), the support structure ST0 having a desired density is easily formed on the support portion SP0. be able to.

  FIG. 11 described above schematically shows an example in which the density of the dots DT of the support part SP0 is changed according to the position of the support part SP0 in the Z direction. The support part SP0 has a first part SP1 and a second part SP2 closer to the overhang part OB2 (three-dimensional object Obj) than the first part SP1 in the Z direction stacked on the first part SP1. Yes. The boundary between the first part SP1 and the second part SP2 in the Z direction is not particularly limited, but a predetermined ratio (for example, 0.3 to 0) from the bottom relative to the height of the support part SP0 such as an intermediate position in the Z direction of the support part SP0. 7), a position separated from the overhang portion OB2 by a predetermined number of voxels in the Z direction, and the like. In the first part SP1 that is relatively far from the overhang portion OB2, the dots DT are made relatively dense (for example, the dot formation rate is 50%), and the column K0 is made relatively thick. In the second portion SP2 that is relatively close to the overhang portion OB2, the dots DT are relatively low in density (for example, the dot formation rate is 25%), and the column K0 is relatively thin. Thereby, it is possible to easily remove the support structure ST0 while reliably supporting the overhang portion OB2.

FIG. 20 shows another specific example of the support forming layer original data generation process performed by the halftone processing unit 95 in S104 of FIG.
When the process is started, the halftone processing unit 95 sets the modeling layer LY [q] to be subjected to the halftone process (S322). Next, the halftone processing unit 95 sets a processing target voxel position (x, y) from all the voxel positions included in the modeling layer LY [q] of the support unit SP0 (S324). After setting the voxel position, the halftone processing unit 95 obtains the number of voxels N1 in the Z direction from the set voxel position (x, y) to the overhang portion OB2 (S326).

  After obtaining the number of voxels N1 of the overhang portion OB2, the halftone processing unit 95 sets an intensity index value ST that specifies the strength required to support the overhang portion OB2 based on the number of voxels N1 (S328). . For example, as shown in FIG. 20, when integer values N01, N02, and N03 satisfy 1 <N01 <N02 <N03, ST = 1 (relatively low intensity) and N01 ≦ N1 when 1 ≦ N1 <N01 When <N02, ST = 2 (medium strength), when N02 ≦ N1 <N03, ST = 3 (relatively high strength), and the like.

After setting the intensity index value ST, the halftone processing unit 95 determines whether all voxel positions have been set (S330). If there are remaining unset voxel positions, the halftone processing unit 95 repeats the processes of S324 to S330. When all the voxel positions are set, the halftone processing unit 95 determines whether all the modeling layers LY [q] are set (S332). When q <Q, the halftone processing unit 95 repeats the processes of S322 to S332. When q = Q, the halftone processing unit 95 generates support unit modeling layer source data OD [1], OD [2],... based on the intensity index value ST and the model data Dat (S334), and supports The part modeling layer source data generation process is terminated. For example, as shown in FIG. 20, the input value V2 (support portion modeling layer original data OD) of the portion where the strength index value ST is “1” (relatively low strength) is a value corresponding to a dot formation rate of 12.5%. (For example, gradation value 32), the input value V2 (supporting part forming layer original data OD) of the portion where the intensity index value ST is “2” (medium intensity) is a value equivalent to 25% (for example, gradation value 64). ), The input value V2 (supporting part forming layer original data OD) of the portion where the strength index value ST is “3” (relatively high strength) may be set to a value equivalent to 50% (for example, gradation value 128), and the like. .
Thereafter, the processing of S106 to S114 in FIG. 6 is performed, and the support SP0 having the dot formation rate corresponding to the three-dimensional object Obj and the input value V2 is formed.

  With the above processing, the input value V2 is set so that the support structure ST0 in which the dot density of the second part SP2 is lower than the dot density of the first part SP1 is formed, and the dot DT of the support part SP0 is set according to this setting. Arranged in a voxel set. Since the density of the dots DT of the second part SP2 closer to the three-dimensional object Obj than the first part SP1 is lower than the density of the dots DT of the first part SP1 in the support part SP0, this specific example is changed from the three-dimensional object to the support part. Can be easily removed.

(9) Seventh processing example of the three-dimensional object forming apparatus:
By the way, the halftone process is not limited to the dither method using a dither mask, but may be an error diffusion method or the like. Therefore, in the modeling process shown in FIG. 6, the support portion halftone process of S106 can be performed by the error diffusion method instead of the systematic dither method.
FIG. 21 schematically shows an example of the support portion halftone process that can be executed in S106 of FIG. In this example, a state where the support structure ST0 is formed on the support part SP0 by the halftone process of the error diffusion method is shown. Various known error diffusion methods used for image processing can be applied to this error diffusion method.

  First, an example of the error diffusion method will be described. In the upper left of FIG. 21, the support layer modeling layer original data OD [q] of the qth layer is schematically shown, and the setting order of the setting voxel PX0 is also schematically shown. In the upper right of FIG. 21, the set voxel PX0 and the voxels PX1 to PX8 adjacent to the set voxel PX0 in the q-th modeling layer LY [q] are schematically illustrated. Here, the upper stage of the set voxel PX0 indicates the input value V2 (155 in FIG. 21) of the support part modeling layer original data OD [q], and the lower stage of the set voxel PX0 indicates an error diffused from other voxels (FIG. 21). Then, 200) is shown. The adjacent voxels PX5 to PX8 are already set voxels, and in this example, the adjacent voxels PX5 and PX7 in which the gradation value 255 indicating the presence of dots is stored are voxels having the dots and the gradation values indicating the absence of dots. Adjacent voxels PX6 and PX8 in which 0 is stored are voxels without dots. The adjacent voxels PX1 to PX4 are voxels that have not been set yet, and are voxels capable of diffusing the error ER from the set voxel PX0. The upper stage of each adjacent voxel PX1 to PX4 shows the input value V2 of the support part forming layer original data OD [q], and the lower stage of each adjacent voxel PX1 to PX4 shows an error 0 that has not yet been diffused.

  Since the gradation value of the set voxel PX0 in which the error has been diffused is 155 + 200 = 355, the error ER = 100 remains even if 255 corresponding to the presence of a dot is subtracted. Therefore, as shown in the lower right of FIG. 21, 255 corresponding to the presence of a dot is left in the set voxel PX0, and the error ER = 100 is diffused to the unconverted voxels PX1 to PX4. Here, the original input value of the setting voxel PX0 is V2, the error diffused in the setting voxel PX0 is ER0, the voxel value when forming the dot DT is Vd (for example, the gradation value 255), and the setting voxel A threshold for dividing whether or not to form a dot DT on PX0 is Vt. For example, when V2 + ER0 ≧ Vt, the value of the set voxel PX0 is converted to Vd, and the error diffused from the set voxel PX0 is ER = V2 + ER0−Vd. When V2 + ER0 <Vt, the value of the set voxel PX0 is converted to 0, and the error diffused from the set voxel PX0 is ER = V2 + ER0.

Here, if the distribution ratio of the error ER is the distribution ratio RD1 shown in FIG. 21, of the error ER = 100 diffused from the set voxel PX0, 60% is diffused to the adjacent voxel PX1, and 10% is distributed to the adjacent voxel PX2. 20% is diffused to adjacent voxel PX3 and 10% is diffused to adjacent voxel PX4.
The voxels for diffusing the error are not limited to the adjacent voxels PX1 to PX4, and may include voxels separated from the set voxel, such as an unconverted voxel in which one adjacent voxel is skipped from the set voxel PX0.

FIG. 22 schematically illustrates an example of an error ER distribution rate. Of course, the distribution rates RD11 to RD15 shown in FIG. 22 are merely examples, and can be changed to various distribution rates. The distribution rate RD11 in the high intensity direction 0 ° is 100% in the distribution to the adjacent voxel PX1, and diffuses all errors from the set voxel PX0 in the 0 ° direction. When the error ER is diffused according to the distribution ratio RD11, the dots DT are easily connected in the 0 ° direction (X direction), and the strength of the support structure ST0 in the 0 ° direction is increased. The distribution rate RD12 in the high intensity direction 45 ° is 100% distributed to the adjacent voxel PX4, and diffuses all errors from the set voxel PX0 in the 45 ° direction. When the error ER is diffused according to the distribution ratio RD12, the dots DT are easily connected in the 45 ° direction, and the strength of the support structure ST0 in the 45 ° direction is increased. The distribution rate RD13 in the high intensity direction 90 ° is 100% distributed to the adjacent voxel PX3, and diffuses all errors from the set voxel PX0 in the 90 ° direction. When the error ER is diffused according to the distribution ratio RD13, the dots DT are easily connected in the 90 ° direction (Y direction), and the strength of the support structure ST0 in the 90 ° direction is increased. The distribution rate RD14 in the high-intensity direction 135 ° is 100% distributed to the adjacent voxel PX2, and diffuses all errors from the set voxel PX0 in the 135 ° direction. When the error ER is diffused according to the distribution ratio RD14, the dots DT are easily connected in the 135 ° direction, and the strength of the support structure ST0 in the 135 ° direction is increased.
Note that the distribution rate applicable to the present technology may not have directivity like the distribution rate RD15. The distribution rates RD11 to RD15 are stored in the storage unit 94, for example.

FIG. 23 shows a specific example of the error diffusion method of the support halftone processing performed by the halftone processing unit 95 in S106 of FIG.
When the process is started, the halftone processing unit 95 sets the modeling layer LY [q] to be subjected to the halftone process (S402). Next, the halftone processing unit 95 secures an area for storing the error ER0 (x, y) diffused in each voxel Vx of the modeling layer LY [q] in the RAM of the host device 9 (S404). . In addition, the halftone processing unit 95 sets a voxel position (x, y) to be processed from all the voxel positions included in the modeling layer LY [q] of the support part SP0 (S406).

  After the setting of the voxel position, the halftone processing unit 95 includes the sum of the input value V2 (x, y) and the diffusion error ER0 (x, y) of the set voxel position (x, y), a predetermined threshold value Vt, The process is branched according to the magnitude relationship (S408). For example, when V2 (x, y) + ER0 (x, y) ≧ Vt, the halftone processing unit 95 represents that there is a dot at the set voxel position (x, y) of the support unit modeling layer data SD [q]. Data Vd is stored, and error ER = V2 (x, y) + ER0 (x, y) −Vd is calculated (S410). When V2 (x, y) + ER0 (x, y) <Vt, the halftone processing unit 95 is data 0 indicating no dot at the set voxel position (x, y) of the support forming layer data SD [q]. And calculate error ER = V2 (x, y) + ER0 (x, y) (S412).

  After that, the halftone processing unit 95 diffuses the error ER to unconverted voxels (for example, adjacent voxels PX1 to PX4) according to the distribution ratio of the error ER (for example, any one of the distribution ratios RD11 to RD15) (S414). After the error ER is diffused, the halftone processing unit 95 determines whether all the voxel positions are set (S416). When the unset voxel position remains, the halftone processing unit 95 repeats the processes of S404 to S416. When all the voxel positions are set, the halftone processing unit 95 determines whether all the modeling layers LY [q] are set (S418). When q <Q, the halftone processing unit 95 repeats the processes of S402 to S418. When q = Q, the halftone processing unit 95 ends the support unit halftone process. Then, the process of S108-S114 of FIG. 6 is performed, and it will be in the state by which the solid object Obj and support part SP0 in which modeling layer LY [q] were laminated | stacked in order are mounted on the modeling stand 45. FIG.

Through the above processing, the halftone process in which the error ER is diffused to the unconverted voxel with respect to the input value V2 representing the dot formation rate in the voxel Vx included in the voxel set representing the support SP0 by the support SP0. Done. Accordingly, the dots DT are arranged in the voxel set of the support part SP0 so that the support structure ST0 that supports the three-dimensional object Obj is formed.
For example, when the input value V2 of each support part modeling layer original data OD [q] is the same value, the obtained support part modeling layer data SD [q] is the same, so the voxel position where the dot DT is formed The dots DT are continuously formed in the Z direction, and the dots are not continuously formed in the Z direction at the voxel positions where the dots are not formed. As a result, as shown in FIG. 10, one or more columns K0 extending in the Z direction are formed on the support portion SP0 as the support structure ST0.

  From the above, for example, when the input value V2 is changed so as to increase the dot formation rate, the density of the dots DT of the support structure ST0 increases. When the input value V2 is changed so as to reduce the dot formation rate, the density of the dots DT of the support structure ST0 decreases. Therefore, the present specific example can provide a technique capable of easily controlling the density of the support portion of the three-dimensional object.

  Note that the above-described distribution rates RD11 to RD14 may be selected according to the setting direction DS1. This process can be similar to the process shown in FIG. First, after generating the support part modeling layer original data OD in S104, the halftone processing part 95 receives the setting direction DS1 giving priority to securing the strength of the support part SP0 from the display operation part 91 (corresponding to S122 in FIG. 13). After receiving the setting direction DS1, the halftone processing unit 95 selects a distribution rate that matches the setting direction DS1 from the distribution rates RD11 to RD14 (corresponding to S124 in FIG. 13). Thereafter, the halftone processing unit 95 performs the support unit halftone process of FIG. 23 using the selected distribution ratio.

Through the above processing, in the modeling layer LY in the support part SP0, the dot DT is set in the setting direction DS1 compared to the input value V2 in the direction (second direction W2) orthogonal to the setting direction DS1 (first direction W1). Halftone processing that is easy to connect is performed. As a result, the number NW1 of struts whose length in the setting direction DS1 is longer than the length in the orthogonal direction (W2) in the cross section is smaller than the number NW2 of columns whose length in the orthogonal direction (W2) is longer than the length in the setting direction DS1. Since it can be increased, the strength of the support structure ST0 in the setting direction DS1 is higher than the strength of the support structure ST0 in the orthogonal direction (W2). As described above, this specific example can control the formation of the support structure in accordance with a direction in which priority is given to securing the strength, and can provide a technique capable of efficiently securing the strength of the three-dimensional support structure.
Of course, the distribution ratio prepared for each direction in which priority is given to securing the strength of the support part SP0 may be two or three, or may be five or more.
Further, the halftone processing of the fourth processing example, the fifth processing example, and the sixth processing example described above can be performed by an error diffusion method instead of the systematic dither method.

(10) Other variations:
Various modifications can be considered for the present invention.
For example, the present technology can also be applied to a three-dimensional object formation apparatus that uses liquids other than C ink, M ink, Y ink, W ink, and CL ink. For example, K (black) ink or the like can be used. Of course, the present technology can also be applied to a three-dimensional object forming apparatus that does not use a part of C ink, M ink, Y ink, W ink, and CL ink.
The liquid discharged from the head unit may be a thermoplastic liquid such as a thermoplastic resin. In this case, the head unit may heat the liquid and discharge it in a molten state. Further, the curing unit may be a portion where the dots from the liquid from the head unit are cooled and solidified in the three-dimensional object forming apparatus. In the present technology, “curing” includes “solidification”. Further, liquids having different types of curing / solidification processes may be used for the modeling ink and the supporting ink (for example, an ultraviolet curable resin is used for the modeling ink and a thermoplastic resin is used for the supporting ink. etc.).

The thickness of the modeling layer may not be uniform.
The support column that supports the three-dimensional object may extend in a direction shifted from the Z direction (the strict lamination direction of the modeling layer).
The curing unit may be mounted on the carriage.
The modeling processing apparatus may form a three-dimensional object by forming a modeling layer by solidifying the powder spread in layers with a curable liquid and laminating the formed modeling layers.
In addition, the three-dimensional object modeling apparatus is not limited to an inkjet type apparatus that forms dots by discharging liquid, but an optical modeling system that forms cured dots by irradiating a tank filled with an ultraviolet curable liquid resin with an ultraviolet laser. Or a powder-sintering lamination-type apparatus that forms a sintered dot by applying a high-power laser beam to a powder material.

  The modeling data generation unit including the halftone processing unit may not be in the host device but may be in the modeling processing device. A model data generation unit that generates model data may also be provided in the modeling processing apparatus without the host apparatus. The display operation unit may not be provided in the host device but may be provided in the modeling processing device.

The above-described processing can be changed as appropriate, for example, by changing the order. For example, in the modeling process of FIG. 6, it is possible to perform the process of generating the support part modeling layer original data OD of S104 before the process of S102 that generates the three-dimensional object modeling layer data BD.
In the above-described determination process, “more than” (≧) is changed to “greater than” (>), “greater than” (>) is changed to “more than” (≧), and “less than” (<). Is changed to “below” (≦), and “below” (≦) is changed to “less than” (<), and is included in the present technology.

(11) Conclusion:
As described above, according to the present invention, it is possible to provide a technique or the like that can easily control the density of the support portion of the three-dimensional object according to various aspects. Needless to say, the above-described basic actions and effects can be obtained even with a technique that does not have the constituent requirements according to the dependent claims but includes only the constituent requirements according to the independent claims.
In addition, the configurations disclosed in the above-described examples are mutually replaced or the combination is changed, the known technology and the configurations disclosed in the above-described examples are mutually replaced or the combinations are changed. The configuration described above can also be implemented. The present invention includes these configurations and the like.

DESCRIPTION OF SYMBOLS 1 ... Modeling processing apparatus, 3 ... Head unit (example of dot formation part), 6 ... Processing control part, 7 ... Position change mechanism, 9 ... Host apparatus, 30 ... Recording head, 31 ... Drive signal generation part, 32 ... Nozzle , 33 ... nozzle surface, 45 ... modeling table, 48 ... ink cartridge (example of liquid cartridge), 60 ... storage unit, 61 ... curing unit, 91 ... display operation unit, 92 ... model data generation unit, 93 ... modeling data Generation unit, 94: storage unit, 95: halftone processing unit, 100: three-dimensional object forming device, BD ... three-dimensional object forming layer data, DS1 ... setting direction, DT ... dot, DT1 ... first dot, DT2 ... second dot , DZ, DZ1, DZ2 ... dither matrix (example of dither mask), Dat ... model data, ER ... error, FD ... modeling layer data, K0, K1-K8, K11, K12 ... strut, LQ Liquid, LQ1 ... modeling ink (example of modeling liquid), LQ2 ... supporting ink (example of supporting liquid), LY ... modeling layer, NW1, NW2 ... number of struts, NZ ... nozzle, Obj ... three-dimensional object, OB1 ... body part, OB2 ... overhang part, OD ... support part modeling layer original data, PR0, PR1, PR2 ... control program, PX0 ... setting voxel, PX1 to PX8 ... voxel, RD1, RD11 to RD15 ... distribution rate, SD ... support part modeling layer data, SP0, SP01, SP02 ... support part, SP1 ... first part, SP2 ... second part, ST0 ... support structure, U1 ... control part, V2 ... input value, Vx ... voxel, W1 ... first One direction, W2 ... second direction.

Claims (11)

A three-dimensional object to be modeled, and a dot forming part for forming dots constituting a support part for supporting the three-dimensional object;
A control unit that controls the modeling of the three-dimensional object and the support unit by the formed dots;
A three-dimensional object shaping apparatus comprising:
In the support unit, a support structure that supports the three-dimensional object is formed in the support unit based on an input value representing a dot formation rate in a voxel included in the voxel set representing the support unit and a dither mask. A three-dimensional object shaping apparatus that arranges dots in the voxel assembly as described above. A three-dimensional object to be modeled, and a dot forming part for forming dots constituting a support part for supporting the three-dimensional object;
A control unit that controls the modeling of the three-dimensional object and the support unit by the formed dots;
A three-dimensional object shaping apparatus comprising:
The control unit performs, in the support unit, halftone processing for diffusing an error into unconverted voxels with respect to an input value indicating a dot formation rate in a voxel included in the voxel set representing the support unit. A three-dimensional object forming apparatus that arranges dots in the voxel assembly such that a support structure for supporting the three-dimensional object is formed. The support structure is one or more columns supporting the three-dimensional object;
The number of pillars whose length in the first direction is longer than the length in the second direction intersecting the first direction in the cross section is the number of pillars whose length in the second direction is longer than the length in the first direction in the cross section. The three-dimensional object shaping apparatus according to claim 1 or 2, wherein the three-dimensional object shaping apparatus is larger than the number. The controller is
Forming the three-dimensional object and the support part by laminating a modeling layer with dots to be formed,
In the modeling layer in the support portion, the support structure is formed by performing a halftone process in which dots are easily connected in the first direction as compared to the second direction intersecting the first direction with respect to the input value. The three-dimensional object modeling apparatus according to claim 1, wherein dots are arranged in the voxel set as described above. The controller is
Forming the three-dimensional object and the support part by laminating a modeling layer with dots to be formed,
In the modeling layer in the support portion, halftone processing is performed in which the dots are more easily connected in the first direction than the second direction intersecting the first direction with respect to the input value, and the dot connection is actually prioritized. The dot is arranged in the voxel set so as to form the support structure by performing a process of rotating the data obtained by the halftone process so that the first direction is directed to a setting direction. Alternatively, the three-dimensional object forming apparatus according to claim 2.   The said control part sets the said input value so that the said support structure of the density based on the information regarding the part supported by the said support part among the said solid objects may be formed, The any one of Claims 1-5 The three-dimensional object shaping apparatus according to claim 1. The support part has a first part and a second part that is closer to the three-dimensional object than the first part in the direction of being stacked on the first part,
The said control part arrange | positions a dot in the said voxel collection so that the density of the dot of said 2nd site | part may become lower than the density of the dot of said 1st site | part in the said support part. The three-dimensional object formation apparatus as described in any one of Claims. A three-dimensional object modeling method for modeling the three-dimensional object and the support part by the dots to be formed using a three-dimensional object to be modeled and a dot forming part for forming dots constituting a support part that supports the three-dimensional object Because
In the support unit, dots are formed so that a support structure for supporting the three-dimensional object is formed based on an input value representing a dot formation rate in a voxel included in the voxel set representing the support unit and a dither mask. A three-dimensional object modeling method, wherein the three-dimensional object and the support part are modeled by being arranged in the voxel assembly. A three-dimensional object modeling method for modeling the three-dimensional object and the support part by the dots to be formed using a three-dimensional object to be modeled and a dot forming part for forming dots constituting a support part that supports the three-dimensional object Because
The support unit performs halftone processing for diffusing an error into unconverted voxels with respect to an input value indicating a dot formation rate in a voxel included in the voxel set representing the support unit, thereby obtaining the three-dimensional object. A three-dimensional object modeling method in which dots are arranged in the voxel assembly so as to form a supporting structure to be supported, and the three-dimensional object and the support part are modeled. A three-dimensional object that includes a three-dimensional object to be modeled and a dot forming unit for forming dots that form a support part that supports the three-dimensional object, and controls the modeling of the three-dimensional object and the support part by the formed dots. A control program for a modeling apparatus,
In the support unit, dots are formed so that a support structure for supporting the three-dimensional object is formed based on an input value representing a dot formation rate in a voxel included in the voxel set representing the support unit and a dither mask. A control program for a three-dimensional object modeling apparatus, which causes a computer to realize a function of arranging in the voxel assembly. A three-dimensional object that includes a three-dimensional object to be modeled and a dot forming unit for forming dots that form a support part that supports the three-dimensional object, and controls the modeling of the three-dimensional object and the support part by the formed dots. A control program for a modeling apparatus,
The support unit performs halftone processing for diffusing an error into unconverted voxels with respect to an input value indicating a dot formation rate in a voxel included in the voxel set representing the support unit, thereby obtaining the three-dimensional object. A control program for a three-dimensional object forming apparatus, which causes a computer to realize a function of arranging dots in the voxel assembly so that a supporting structure to support is formed.

Images